Zorki 3M Lens Flange

[Rob Holland]

I have a Zorki 3M and shot a few rolls through it and all seems fine. The 'problem' is that with the I61 that came with it, the distance markings on the lens face the bottom. I screwed in two I22's and one had the focus lever on the top and the other had the focus lever on the side.

Does the lens flange itself have a proper orientation, or is this odd placement normal?

Any help is much appreciated.

Thanks,
Rob

 

[farlymac]

Could be someone did some repair work on it, and inverted the mounting ring. That's kind of hard to do on the original Zorki's, but the design may have been changed later on, and now allows for this to happen. Or your lenses may have been put back together wrong.

PF

 

[Coldkennels]

It's basically impossible to put an I22 back together wrong, so I don't think that the lenses are to blame. And I don't think the problem is that the lens mount has been inverted due the fact that all three lenses mount in such totally different positions. That's a very weird problem; normally there's some slight variation - maybe a ten-degree shift one way or the other - but nothing that extreme. I have heard of it before, but I have no idea what causes it. I should imagine that just swapping the lens mount should fix it, and it should be relatively easy to find a replacement. I'm sure someone on here will have a spare one they'd be willing to sell/give to you.

Before you do that, though, do you have a different LTM body to try the lenses on? If they all sit properly on another camera then I'd say it's definitely time to start begging for a spare lens mount!

 

[wolves3012]

Roughly speaking, the focus scale ought to be "right way up" when mounted but some variation is pretty normal. What you describe, however, is beyond "normal". The 3M is one of the few FSUs where the lens mount actually *can* be fitted in any orientation, on most models there is only one way to fit it.

The Industar 61 is difficult, if not impossible, to reassemble incorrectly BUT it is possible to move the scales around.

You have 2 possibilities then - the lens or the lens-mount, which isn't helpful. Industar 22s can vary a fair bit so that doesn't help either.

As Coldkennels suggests, you could do with a "definitive" lens to tell you where the problem lies. The solution is pretty simple in either case. Four screws retain the lens-mount (and beware of any shims you might find underneath - where they go when refitted is also a bit of a problem). The lens scales are retained by tiny screws BUT the aperture scale is more problematic. Where does the aperture scale sit at present, does it appear in the same area as the DOF/index (diamond-shaped) mark? If so, the lens is *not* incorrect.

 

[Rob Holland]

Thanks for all of the responses!

Based on Cold's suggestion, I mounted the 3 I-22's and one I-61 that I have to each of the 3 bodies that I have. I recorded the scale position in clock fashion with 12 o'clock being normal and 6 o'clock being down. I also measured and recorded the length of the threaded barrel that screws into the flange.

Fed 3
I-22 #1 12 o'clock
#2 12 o'clock 4.45mm
#3 3 o'clock 3.79mm
I-61 #1 12 o'clock 4.51mm

Zorki 2
I-22 #1 10 o'clock
#2 8 o'clock
#3 11 o'clock
I-61 #1 9 o'clock

Zorki 3M
I-22 #1 6 o'clock
#2 5 o'clock
#3 7 o'clock
I-61 #1 6 o'clock

There seems to be a LOT of variation between the lenses, including the length of the threaded barrels. Looking at the 3M numbers, I'm pretty sure the flange is mounted 180 degrees out of sync.

The variation in the threaded barrel lengths suggest to me that it will be impossible to have all lenses position correctly on all cameras. The barrel apperas to be one piece, so it would take some grinding and re-threading to make them all the same length.

Wolves - I checked the aperture orientation of the 61 and they are on the same side as the distance scales.

All 3 cameras take decent pictures, so this is not really a problem. Just something that caught my attention.

I look forward to hearing your thoughts!

Thanks,
Rob

 

[wolves3012]

Those variations don't surprise me too much, except of course for the 3M. I tend to agree, the mount has been put on upside down. There are some odd disagreements there though all the same but hey, that's FSUs for you! The length of the threaded portion is, to a degree, irrelevant - it's the point at which is stops that matters and you can't easily change it nor would you want to.

Course of action: Lay the 3M on its back. Undo the 4 screws holding the mount in place. Lift off the mount and look for shims underneath. If there's a whole paper shim/shims or no shims (a "whole" shim usually means it goes around all 4 holes but isn't necessarily a complete circle) then turn the mount 180 degrees and replace the screws - do them just lightly then tighten them in an X-pattern in a couple of stages, so you won't distort the mount.

If there's a part shim, leave it in place initially and turn the mount as above. Take a close-up picture of a brick wall or something similar that's flat and has detail, keeping the camera back parallel to the subject (and use a tripod or other steady, to get the sharpest picture possible). Examine the photo under magnification for correct focus all around the frame. If it's not even, take the mount off again and move the shim 180 degrees so it's under the same part of the mount as it was originally before you rotated the mount. Re-check focus. One or other position should be correct. If you can find a suitable screen, you may be able to check focus by putting it across the film rails but keeping the setup aligned on a flat subject might be difficult.

 

[Rob Holland]

Wolves:

I did as you suggested. There is one full shim and a partial shim at the 6 o'clock position. Rotated the flange and placed the partial shim in the 12 o'clock position.

The good news is the I-61 now has the distance marking at the top, dead on the 12 o'clock position. The bad news is I just used my dial indicator to check the registration and it's way off. Not a big deal to re-shim the flange, but I'm too pooped to do it tonight.

I hated to mess with the 3M because I got it from Oleg and it's in very good to excellent condition. The scale at the bottom was just driving me nuts! The shims look original, at least they are the same old hard fiberboard I've seen on others. The other two cameras I'll just fit a lens to them that comes close and leave it at that.

I've been on RFF for about 6 years, but rarely post. I thouroughly enjoy learning about the Russian cameras on this board and am truly amazed at some of the pictures I've seen taken with them.

Thanks again!
Rob

 

[wolves3012]

Wolves:

I did as you suggested. There is one full shim and a partial shim at the 6 o'clock position. Rotated the flange and placed the partial shim in the 12 o'clock position.

The partial shim may have been needed because the body wasn't quite flat or because the mount wasn't quite flat. If the body wasn't flat, then you'll have introduced an error between top and bottom by moving the shim with the mount. If you notice that's the case, move the partial shim back to its original, 6 O'clock position.

Glad that it's solved the problem though! I replaced the curtains on my 3M and noticed the mount had no flat at the top, unlike most models, so I marked the top for correct reassembly. It would be an easy mistake not to have done so.